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Role of social distancing in tackling COVID-19 during the first wave of pandemic in Nordic region:Evidence from daily deaths,infections and needed hospital resources 被引量:1
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作者 Arshia Amiri 《International Journal of Nursing Sciences》 CSCD 2021年第2期145-151,I0001,共8页
Objectives:To measure the effect of social distancing on reducing daily deaths,infections and hospital resources needed for coronavirus disease 2019(COVID-19)patients during the first wave of the pandemic in Nordic co... Objectives:To measure the effect of social distancing on reducing daily deaths,infections and hospital resources needed for coronavirus disease 2019(COVID-19)patients during the first wave of the pandemic in Nordic countries.Methods:The observations of social distancing,daily deaths,infections along with the needed hospital resources for COVID-19 patient hospitalizations including the numbers of all hospital beds,beds needed in ICUs and infection wards,nursing staffs needed in ICUs and infection wards were collected from the Institute for Health Metrics and Evaluation(IHME)by the University of Washington.The observations of social distancing were based on the reduction in human contact relative to background levels for each location quantified by cell phone mobility data collected from IHME.The weighted data per 100,000 population gathered in a 40-day period of the first wave of the pandemic in Denmark,Finland,Iceland,Norway and Sweden.Statistical technique of panel data analysis is used to measure the associations between social distancing and COVID-19 indicators in long-run.Results:Results of dynamic long-run models confirm that a 1%rise in social distancing by reducing human contacts may decline daily deaths,daily infections,all hospital beds needed,beds/nurses needed in ICUs and beds/nurses needed in infection wards due COVID-19 pandemic by 1.13%,15.26%,1.10%,1.17%and 1.89%,respectively.Moreover,results of error correction models verify that if the equilibriums between these series are disrupted by a sudden change in social distancing,the lengths of restoring back to equilibrium are 67,62,40,22 and 49 days for daily deaths,daily infections,all hospital beds needed,nurses/beds needed in ICUs and nurses/beds needed in infection wards,respectively.Conclusion:Proper social distancing was a successful policy for tackling COVID-19 with falling mortality and infection rates as well as the needed hospital resources for patient hospitalizations in Nordic countries.The results alert governments of the need for continuously implementing social distancing policies while using vaccines to prevent national lockdowns and reduce the burden of patient hospitalizations. 展开更多
关键词 COVID-19 Intensive care units Health resources HOSPITALIZATION Mortality Nursing staff Pandemics Physical distancing
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Investigation of Coronavirus Deposition in Realistic Human Nasal Cavity and Impact of Social Distancing to Contain COVID-19:A Computational Fluid Dynamic Approach 被引量:1
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作者 Mohammad Zuber John Valerian Corda +8 位作者 Milad Ahmadi BSatish Shenoy Irfan Anjum Badruddin Ali E.Anqi Kamarul Arifin Ahmad S.M.Abdul Khader Leslie Lewis Mohammad Anas Khan Sarfaraz Kamangar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第12期1185-1199,共15页
The novel coronavirus responsible for COVID-19 has spread to several countries within a considerably short period.The virus gets deposited in the human nasal cavity and moves to the lungs that might be fatal.As per sa... The novel coronavirus responsible for COVID-19 has spread to several countries within a considerably short period.The virus gets deposited in the human nasal cavity and moves to the lungs that might be fatal.As per safety guidelines by theWorld Health Organization(WHO),social distancing has emerged as one of the major factors to avoid the spread of infection.However,different guidelines are being followed across the countries with regards to what should be the safe distance.Thus,the current work is an attempt to understand the virus deposition pattern in the realistic human nasal cavity and also to find the impact of distance that could be termed as a safety measure.This study is performed usingComputationalFluid Dynamics as a solution tool to investigate the impact of COVID-19 deposition(i)On a realistic 3D human upper airway model and(ii)2D social distancing protocol for a distance of 0.6,1.2,1.8,and 2.4 m.The results revealed that the regional deposition flux within the nasal cavity was predominantly observed in the external nasal cavity and nasopharyngeal section.Frequent flushing of these regions with saltwater substitutes can limit contamination in healthy individuals.The safe distancing limit estimated with 1 m/s airflow was about 1.8 m.The extensive deposition was observed for distances less than 1.8 m in this study,emphasizing the fact that social distancing advisories are not useful and do not take into account the external dynamics associated with airflow. 展开更多
关键词 COVID-19 upper respiratory tract virus deposition social distancing
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Clustering Indoor Location Data for Social Distancing and Human Mobility to Combat COVID-19
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作者 Yuan Ai Ho Chee Keong Tan Yin Hoe Ng 《Computers, Materials & Continua》 SCIE EI 2022年第4期907-924,共18页
The world is experiencing the unprecedented time of a pandemic caused by the coronavirus disease(i.e.,COVID-19).As a countermeasure,contact tracing and social distancing are essential to prevent the transmission of th... The world is experiencing the unprecedented time of a pandemic caused by the coronavirus disease(i.e.,COVID-19).As a countermeasure,contact tracing and social distancing are essential to prevent the transmission of the virus,which can be achieved using indoor location analytics.Based on the indoor location analytics,the human mobility on a site can be monitored and planned to minimize human’s contact and enforce social distancing to contain the transmission of COVID-19.Given the indoor location data,the clustering can be applied to cluster spatial data,spatio-temporal data and movement behavior features for proximity detection or contact tracing applications.More specifically,we propose the Coherent Moving Cluster(CMC)algorithm for contact tracing,the density-based clustering(DBScan)algorithm for identification of hotspots and the trajectory clustering(TRACLUS)algorithm for clustering indoor trajectories.The feature extraction mechanism is then developed to extract useful and valuable features that can assist the proposed system to construct the network of users based on the similarity of the movement behaviors of the users.The network of users is used to model an optimization problem to manage the human mobility on a site.The objective function is formulated to minimize the probability of contact between the users and the optimization problem is solved using the proposed effective scheduling solution based on OR-Tools.The simulation results show that the proposed indoor location analytics system outperforms the existing clustering methods by about 30%in terms of accuracy of clustering trajectories.By adopting this system for human mobility management,the count of close contacts among the users within a confined area can be reduced by 80%in the scenario where all users are allowed to access the site. 展开更多
关键词 Indoor location analytics COVID-19 contact tracing social distancing spatial-temporal dimensions human mobility
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Blockchain and IIoT Enabled Solution for Social Distancing and Isolation Management to Prevent Pandemics
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作者 Muhammad Saad Maaz Bin Ahmad +4 位作者 Muhammad Asif Muhammad Khalid Khan Toqeer Mahmood Elsayed Tag Eldin Hala Abdel Hameed 《Computers, Materials & Continua》 SCIE EI 2023年第7期687-709,共23页
Pandemics have always been a nightmare for humanity,especially in developing countries.Forced lockdowns are considered one of the effective ways to deal with spreading such pandemics.Still,developing countries cannot ... Pandemics have always been a nightmare for humanity,especially in developing countries.Forced lockdowns are considered one of the effective ways to deal with spreading such pandemics.Still,developing countries cannot afford such solutions because these may severely damage the country’s econ-omy.Therefore,this study presents the proactive technological mechanisms for business organizations to run their standard business processes during pandemic-like situations smoothly.The novelty of this study is to provide a state-of-the-art solution to prevent pandemics using industrial internet of things(IIoT)and blockchain-enabled technologies.Compared to existing studies,the immutable and tamper-proof contact tracing and quarantine management solution is proposed.The use of advanced technologies and information security is a critical area for practitioners in the internet of things(IoT)and corresponding solutions.Therefore,this study also emphasizes information security,end-to-end solution,and experimental results.Firstly,a wearable wristband is proposed,incorporating 4G-enabled ultra-wideband(UWB)technology for smart contact tracing mechanisms in industries to comply with standard operating procedures outlined by the world health organization(WHO).Secondly,distributed ledger technology(DLT)omits the centralized dependency for transmitting contact tracing data.Thirdly,a privacy-preserving tracing mechanism is discussed using a public/private key cryptography-based authentication mechanism.Lastly,based on geofencing techniques,blockchain-enabled machine-to-machine(M2M)technology is proposed for quarantine management.The step-by-step methodology and test results are proposed to ensure contact tracing and quarantine management.Unlike existing research studies,the security aspect is also considered in the realm of blockchain.The practical implementation of the proposed solution also obtains the results.The results indicate the successful implementation of blockchain-enabled contact tracing and isolation management using IoT and geo-fencing techniques,which could help battle pandemic situations.Researchers can also consider the 5G-enabled narrowband internet of things(NB-IoT)technologies to implement contact tracing solutions. 展开更多
关键词 Blockchain contact tracing distributed ledger technology geo-fencing internet of things industrial internet of things isolation management social distancing ULTRA-WIDEBAND
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A Real-Time Pedestrian Social Distancing Risk Alert System for COVID-19
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作者 Zhihan Liu Xiang Li +3 位作者 Siqi Liu Wei Li Xiangxu Meng Jing Jia 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期937-954,共18页
The COVID-19 virus is usually spread by small droplets when talking,coughing and sneezing,so maintaining physical distance between people is necessary to slow the spread of the virus.The World Health Organization(WHO)... The COVID-19 virus is usually spread by small droplets when talking,coughing and sneezing,so maintaining physical distance between people is necessary to slow the spread of the virus.The World Health Organization(WHO)recommends maintaining a social distance of at least six feet.In this paper,we developed a real-time pedestrian social distance risk alert system for COVID-19,whichmonitors the distance between people in real-time via video streaming and provides risk alerts to the person in charge,thus avoiding the problem of too close social distance between pedestrians in public places.We design a lightweight convolutional neural network architecture to detect the distance between people more accurately.In addition,due to the limitation of camera placement,the previous algorithm based on flat view is not applicable to the social distance calculation for cameras,so we designed and developed a perspective conversion module to reduce the image in the video to a bird’s eye view,which can avoid the error caused by the elevation view and thus provide accurate risk indication to the user.We selected images containing only person labels in theCOCO2017 dataset to train our networkmodel.The experimental results show that our network model achieves 82.3%detection accuracy and performs significantly better than other mainstream network architectures in the three metrics of Recall,Precision and mAP,proving the effectiveness of our system and the efficiency of our technology. 展开更多
关键词 Convolutional neural network pedestrian detection social distancing COVID-19
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Stigma of Mental Illness: Social Distancing Attitudes among Registered Nurses in Australia
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作者 Tan Kan Ku Michael Ha 《Journal of Biosciences and Medicines》 2015年第12期40-47,共8页
Background: Stigma of mental illness is often examined in social psychology and psychiatric rehabilitation using attitude studies. Participants of these studies are among health professionals and general public member... Background: Stigma of mental illness is often examined in social psychology and psychiatric rehabilitation using attitude studies. Participants of these studies are among health professionals and general public members. A common measure of stigma is using validated scale which measures the opinion on mental illness. Method: A cross-sectional survey was presented to 208 registered nurses. Principal component analyses (with oblique rotation) were used to identify underlying dimensionality in the correlations of items for social distancing. Subscale score variations were analysed across nurse type and ethnicity to examine the discriminant validity of the subscale. Results: Principal component analysis (PCA) revealed one dimension accounting for 43.5% of the variations within items for social distancing. Developed as scale, termed Stigma towards Psychiatric Patients (STPP), reliability analysis indicated high internal consistency with respective alpha coefficient of 0.8. Chinese general nurses scored highest on social distancing than the other three groups: Chinese psychiatric nurses, Anglo general and Anglo psychiatric nurses. Conclusion: Psychometric evaluation of the Stigma Scale (STPP) suggests it is a reliable instrument for measuring social distancing attitudes towards mental illness. The effect of ethnicity on stigmatising attitudes is not entirely accounted for by exposure to people with mental illness. 展开更多
关键词 STIGMA MENTAL Illness SOCIAL distancing
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The Local Wisdom of Balala Tamakng Custom in Social Distancing During the Covid-19 Pandemic
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作者 Yohanes Bahari 《Sociology Study》 2021年第3期112-121,共10页
This study aims to describe the local wisdom of balala tamakng custom in social distancing during the Covid-19 pandemic.The research approach used was descriptive qualitative with an ethnographic method.The informants... This study aims to describe the local wisdom of balala tamakng custom in social distancing during the Covid-19 pandemic.The research approach used was descriptive qualitative with an ethnographic method.The informants participated were Dayak customary officials.The data collection used was deep interview,and data were validated using sources triangulation,and were analyzed by data reduction,data display,and conclusion drawing.The general conclusion of this research:Balala as a local wisdom in maintaining the balance between humans and the nature that has been passed down from generation to generation is still carried out today.The specific conclusions of this study:(1)Balala is the custom of abstinence in the Kanayatn Dayak community;(2)balala consists of regular balala and balala tamakng;(3)balala tamakng has the meaning as a means of creating a balance between human relations and the universe;(4)there is no direct relationship between the custom of balala tamakng with social and physical distancing against Covid-19. 展开更多
关键词 balala tamakng local wisdom social distancing
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Alert Device for Social Distancing
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作者 Amer Nizar AbuAli 《Communications and Network》 2024年第2期31-50,共20页
Social distancing among people is vital in minimizing spread of COVID-19 within community and can be effective in flattening the outbreak. This research work focuses on developing a close contact proximity detection s... Social distancing among people is vital in minimizing spread of COVID-19 within community and can be effective in flattening the outbreak. This research work focuses on developing a close contact proximity detection system among smartphone users, particularly of COVID-19 patient, using Bluetooth signal to identify and analyze close contact proximity and social distancing from other anonymous smartphone users in their surroundings. Covering a physical space of six feet, a mandatory safety measure in shopping centers, schools, and other crowded areas, is a social solution advocated by World Health Organization (WHO) officials in this COVID-19. Everyone is concerned about their safety in the COVID-19 environment, so we came up with the concept of producing this new equipment. Most of the time, our attention is drawn to those in front of us and to our sides, but we are unable to keep track of those behind us. The major goal of this project is to keep individuals at a safe distance from one another. PIR sensor is used in this proposed work. Why did the World Health Organization (WHO) put 6 feet as a social distancing? When someone coughs or sneezes, small droplets are spread from the cough or sneeze. If you are in close proximity, you can breathe in those droplets, which may contain the COVID-19 virus, according to the World Health Organization. Vanderbilt University infectious disease expert Dr. William Schaffner said the “6 feet distance” rule comes from studies of respiratory physiology. Schaffner explains that even “without a cough or sneeze, the exhaled air mixes with the surrounding air within a distance of 3 to 6 feet, which is known as the breathing zone.” Schaffner continues: “If you are standing 3 to 6 feet away from me, you may inhale droplets that spread through coughing or sneezing. Of course, if I am infected with the virus, these droplets will contain the virus.” 展开更多
关键词 Social distancing COVID-19 Pandemic
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Social Distancing and Isolation Management Using Machine-to-Machine Technologies to Prevent Pandemics 被引量:2
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作者 Muhammad Saad Maaz Bin Ahmad +2 位作者 Muhammad Asif Khalid Masood Mohammad A.Al Ghamdi 《Computers, Materials & Continua》 SCIE EI 2021年第6期3545-3562,共18页
Social distancing and self-isolation management are crucial preventive measures that can save millions of lives during challenging pandemics of diseases such as the Spanish u,swine u,and coronavirus disease 2019(COVID... Social distancing and self-isolation management are crucial preventive measures that can save millions of lives during challenging pandemics of diseases such as the Spanish u,swine u,and coronavirus disease 2019(COVID-19).This study describes the comprehensive and effective implementation of the Industrial Internet of Things and machine-to-machine technologies for social distancing and smart self-isolation management.These technologies can help prevent outbreaks of any disease that can disperse widely and develop into a pandemic.Initially,a smart wristband is proposed that incorporates Bluetooth beacon technology to facilitate the tracing and tracking of Bluetooth Low Energy beacon packets for smart contact tracing.Second,the connectivity of the device with Android or iOS applications using long-term evolution technology is realized to achieve mobility.Finally,mathematical formulations are proposed to measure the distance between coordinates in order to detect geo-fencing violations.These formulations are specically designed for the virtual circular and polygonal boundaries used to restrict suspected or infected persons from trespassing in predetermined areas,e.g.,at home,in a hospital,or in an isolation ward.The proposed framework outperforms existing solutions,since it is implemented on a wider scale,provides a range of functionalities,and is cost-effective. 展开更多
关键词 Coronavirus disease 2019 PANDEMIC machine-to-machine industrial internet of things social distance geo-fencing
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A Hybrid Heuristic Algorithm for Solving COVID-19’s Social Distancing at Universities Campus
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作者 Hassan Al-Tarawneh Khalid Al-Kaabneh +2 位作者 Aysh Alhroob Hazem Migdady Issam Alhadid 《Computer Systems Science & Engineering》 SCIE EI 2022年第6期933-944,共12页
Social distancing during COVID-19 has become one of the most important measures in reducing the risks of the spread of the virus. Implementing thesemeasures at universities is crucial and directly related to the physi... Social distancing during COVID-19 has become one of the most important measures in reducing the risks of the spread of the virus. Implementing thesemeasures at universities is crucial and directly related to the physical attendance ofthe populations of students, professors, employees, and other members on campus. This research proposes an automated scheduling approach that can help universities and schools comply with the social distancing regulations by providingassistance in avoiding huge assemblages of people. Furthermore, this paper proposes a novel course timetable-scheduling scheme based on four main constraints.First, a distance of two meters must be maintained between each student inside theclassroom. Second, no classrooms should contain more than 20% of their regularcapacity. Third, there would be no back-to-back classes. Lastly, no lectures shouldbe held simultaneously in adjacent classrooms. The proposed approach wasimplemented using a variable neighborhood search (VNS) approach with an adaptive neighborhood structure (AD-NS) to resolve the problem of scheduling coursetimetables at Al-Ahlyyia Amman University. However, the experimental resultsshow that the proposed techniques outperformed the standard VNS tested on university course timetabling benchmark dataset ITC2007-Track3. Meanwhile, theapproach was tested using datasets collected from the faculty of information technology at Al-Ahlyyia Amman University (Jordan). Where the results showed that,the proposed technique could help educational institutes to resume their regularoperations while complying with the social distancing guidelines. 展开更多
关键词 COVID-19 social distance variable neighborhood search adaptive neighborhood structure university course timetable
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Social distancing and testing as optimal strategies against the spread of COVID-19 in the Rio Grande Valley of Texas 被引量:2
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作者 Kristina P.Vatcheva Josef Sifuentes +3 位作者 Tamer Oraby Jose Campo Maldonado Timothy Huber María Cristina Villalobos 《Infectious Disease Modelling》 2021年第1期729-742,共14页
At the beginning of August 2020,the Rio Grande Valley(RGV)of Texas experienced a rapid increase of coronavirus disease 2019(abbreviated as COVID-19)cases and deaths.This study aims to determine the optimal levels of e... At the beginning of August 2020,the Rio Grande Valley(RGV)of Texas experienced a rapid increase of coronavirus disease 2019(abbreviated as COVID-19)cases and deaths.This study aims to determine the optimal levels of effective social distancing and testing to slow the virus spread at the outset of the pandemic.We use an age-stratified eight compartment epidemiological model to depict COVID-19 transmission in the community and within households.With a simulated 120-day outbreak period data we obtain a post 180-days period optimal control strategy solution.Our results show that easing social distancing between adults by the end of the 180-day period requires very strict testing a month later and then daily testing rates of 5%followed by isolation of positive cases.Relaxing social distancing rates in adults from 50%to 25%requires both children and seniors to maintain social distancing rates of 50%for nearly the entire period while maintaining maximum testing rates of children and seniors for 150 of the 180 days considered in this model.Children have higher contact rates which leads to transmission based on our model,emphasizing the need for caution when considering school reopenings. 展开更多
关键词 COVID-19 Mathematical modeling Optimal control Rio Grande Valley(RGV) Testing and social distancing School reopening
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Social Distancing,Labor Market Outcomes,and Job Characteristics in the COVID-19 Pandemic 被引量:1
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作者 Suqin Ge Yu Zhou 《Frontiers of Economics in China-Selected Publications from Chinese Universities》 2020年第4期478-520,共43页
This study investigates the role of job characteristics on an individual’s decisions to follow social distancing policies,work,and apply for unemployment insurance in the United States during the COVID-19 pandemic.We... This study investigates the role of job characteristics on an individual’s decisions to follow social distancing policies,work,and apply for unemployment insurance in the United States during the COVID-19 pandemic.We use data that track millions of mobile devices and their daily movements across physical locations to measure whether the devices’owners leave their homes,or work part-time or fulltime on a given day,and we also collect data on weekly unemployment insurance claims.We find that the presence of jobs with a high work-ffom-home capacity in a region increases the ability of people to follow social distancing policies and decreases their unemployment risk,whereas the presence of jobs with high physical proximity decreases the incidences of following social distancing policies and unemployment and increases the incidence of work during the pandemic.These heterogeneous responses based on local job characteristics persist even conditional on a broad set of demographic and socioeconomic variables. 展开更多
关键词 work-from-home physical proximity social distancing EMPLOYMENT COVID-19
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Widespread testing, case isolation and contact tracing may allow safe school reopening with continued moderate physical distancing: A modeling analysis of King County, WA data
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作者 Chloe Bracis Eileen Burns +4 位作者 Mia Moore David Swan Daniel B.Reeves Joshua T.Schiffer Dobromir Dimitrov 《Infectious Disease Modelling》 2021年第1期24-35,共12页
Background:In late March 2020,a“Stay Home,Stay Healthy”order was issued in Washington State in response to the COVID-19 pandemic.On May 1,a 4-phase reopening plan began.We investigated whether adjunctive prevention ... Background:In late March 2020,a“Stay Home,Stay Healthy”order was issued in Washington State in response to the COVID-19 pandemic.On May 1,a 4-phase reopening plan began.We investigated whether adjunctive prevention strategies would allow less restrictive physical distancing to avoid second epidemic waves and secure safe school reopening.Methods:We developed a mathematical model,stratifying the population by age,infection status and treatment status to project SARS-CoV-2 transmission during and after the reopening period.The model was parameterized with demographic and contact data from King County,WA and calibrated to confirmed cases,deaths and epidemic peak timing.Adjunctive prevention interventions were simulated assuming different levels of pre-COVID physical interactions(pC_PI)restored.Results:The best model fit estimated~35%pC_PI under the lockdown which prevented~17,000 deaths by May 15.Gradually restoring 75%pC_PI for all age groups between May 15-July 15 would have resulted in~350 daily deaths by early September 2020.Maintaining<45%pC_PI was required with current testing practices to ensure low levels of daily infections and deaths.Increased testing,isolation of symptomatic infections,and contact tracing permitted 60%pC_PI without significant increases in daily deaths before November and allowed opening of schools with<15 daily deaths.Inpatient antiviral treatment was predicted to reduce deaths significantly without lowering cases or hospitalizations.Conclusions:We predict that widespread testing,contact tracing and case isolation would allow relaxation of physical distancing,as well as opening of schools,without a surge in local cases and deaths. 展开更多
关键词 Mathematical modeling Epidemiology Age structured model Physical distancing Contact tracing
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Modeling the impact of surveillance activities combined with physical distancing interventions on COVID-19 epidemics at a local level
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作者 Guan-Jhou Chen John RBPalmer +1 位作者 Frederic Bartumeus Ana Alba-Casals 《Infectious Disease Modelling》 2022年第4期811-822,共12页
Physical distancing and contact tracing are two key components in controlling the COVID-19 epidemics.Understanding their interaction at local level is important for policymakers.We propose a flexible modeling framewor... Physical distancing and contact tracing are two key components in controlling the COVID-19 epidemics.Understanding their interaction at local level is important for policymakers.We propose a flexible modeling framework to assess the effect of combining contact tracing with different physical distancing strategies.Using scenario tree analyses,we compute the probability of COVID-19 detection using passive surveillance,with and without contact tracing,in metropolitan Barcelona.The estimates of detection probability and the frequency of daily social contacts are fitted into an age-structured susceptible-exposed-infectious-recovered compartmental model to simulate the epidemics considering different physical distancing scenarios over a period of 26 weeks.With the original Wuhan strain,the probability of detecting an infected individual without implementing physical distancing would have been 0.465,0.515,0.617,and 0.665 in designated age groups(0e14,15e49,50e64,and>65),respectively.As the physical distancing measures were reinforced and the disease circulation decreased,the interaction between the two interventions resulted in a reduction of the detection probabilities;however,despite this reduction,active contact tracing and isolation remained an effective supplement to physical distancing.If we relied solely on passive surveillance for diagnosing COVID-19,the model required a minimal 50%(95%credible interval,39e69%)reduction of daily social contacts to keep the infected population under 5%,as compared to the 36%(95%credible interval,22e56%)reduction with contact tracing systems.The simulation with the B.1.1.7 and B.1.167.2 strains shows similar results.Our simulations showed that a functioning contact tracing program would reduce the need for physical distancing and mitigate the COVID-19 epidemics. 展开更多
关键词 SARS-CoV-2 Physical distancing Social mixing pattern Contact tracing Scenario tree analysis
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A Journey Across Africa
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作者 YANG CHAOHUI HUA GUANGCAN 《ChinAfrica》 2026年第3期58-59,共2页
Despite the geographical distance between China and Africa,the rich customs and lifestyles of the African people present an interesting area of study for international professionals.It is this facet of Africa that fas... Despite the geographical distance between China and Africa,the rich customs and lifestyles of the African people present an interesting area of study for international professionals.It is this facet of Africa that fascinated us most during our research journey across the continent. 展开更多
关键词 AFRICA china research journey CUSTOMS international professionals lifestyles geographical distance
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A dose-response curve of restorative benefits of plant communities:based on visual distances and yellow to green hue range
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作者 Yanming Ding Hongxin Qu Haiyan Qu 《Journal of Forestry Research》 2026年第2期239-259,共21页
Urban green spaces have positive effects on both physical and mental wellbeing.However,few studies have focused on the trends and thresholds of the effects of different influences on restorative benefits when viewing ... Urban green spaces have positive effects on both physical and mental wellbeing.However,few studies have focused on the trends and thresholds of the effects of different influences on restorative benefits when viewing scenes differfeaturing plant communities.We measured subjective evaluations and objective physiological data from 44 participants who viewed images of plant communities in the yellow to green hue range to compare differences in restorative benefits among plant communities at different visual distances,as well as quantifying the influencing factors involved.The following results were found:(1)Coniferous and multi-layered plant communities were found to provide greater restorative benefits,and the restorative benefits grew with increasing visual distance.(2)Shape and color characteristics were significantly correlated with restorative benefits,but the relationship is not simply linear.(3)The restorative benefits were found to be greatest when crown proportion was 61.23%,trunk proportion ranged from 4.11%to 13.70%,and the value of color index value ranged from 25.44%to 35.56%;the restorative benefits gradually increased when sky proportion exceeded 12.95%-13.19%,the fractal dimension exceeded 1.62-1.67,and hue index exceeded 91.64°-95.67°;additionally,the restorative benefits decreased when the saturation index increased.This study provides a scientific basis for the construction and improvement of plant landscapes in urban green spaces. 展开更多
关键词 Plant community Visual distance Restorative benefits EEG THRESHOLD
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Rational design of atomic skin layers with low Ir-Ir atomic distance for highly efficient OER catalysts
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作者 Zhen Zeng Yuling Hu +6 位作者 Yun Liu Hao Zhang Wenjuan Shi Zhenye Kang Yuliang Yuan Wei Sun Xinlong Tian 《Science China Materials》 2026年第3期1448-1455,共8页
The development of catalysts with highly efficient oxygen evolution performance and low-Ir loading is key to scaling up the application of proton exchange membrane(PEM)water electrolysis technology.Here,an Ir-skin cat... The development of catalysts with highly efficient oxygen evolution performance and low-Ir loading is key to scaling up the application of proton exchange membrane(PEM)water electrolysis technology.Here,an Ir-skin catalyst(Ir@KM)is realized on a potassium-manganese oxide(K_(0.25)MnO_(x)(KM))using an ion-exchange method.The Ir-skin over the prepared Ir@KM has a low Ir-Ir atomic distance,endowing an energetically favorable oxide path mechanism to allow a low theoretical overpotential of 0.13 V.Ir@KM offers a low overpotential of~280 mV at a current density of 10 mA cm^(-2)and provides a high mass activity of up to 18,500 A at a cell voltage of 1.8 V in PEM,which is 17.6 times higher than that of IrO_(2),demonstrating a significant advantage in reducing the cost of the membrane electrode.The presented Ir-skin concept represents a promising strategy to fabricate low-Ir catalyst with high activity and durability for practical applications of PEM. 展开更多
关键词 OER Ir-based oxides skin catalyst low atomic distance PEM
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Solving Multi-Depot Vehicle Routing Problems with Dynamic Customer Demand Using a Scheduling System TS-DPU Based on TS-ACO
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作者 Tsu-Yang Wu Chengyuan Yu +2 位作者 Yanan Zhao Saru Kumari Chien-Ming Chen 《Computers, Materials & Continua》 2026年第3期2244-2268,共25页
With the increasing complexity of logistics operations,traditional static vehicle routing models are no longer sufficient.In practice,customer demands often arise dynamically,and multi-depot systems are commonly used ... With the increasing complexity of logistics operations,traditional static vehicle routing models are no longer sufficient.In practice,customer demands often arise dynamically,and multi-depot systems are commonly used to improve efficiency.This paper first introduces a vehicle routing problem with the goal of minimizing operating costs in a multi-depot environment with dynamic demand.New customers appear in the delivery process at any time and are periodically optimized according to time slices.Then,we propose a scheduling system TS-DPU based on an improved ant colony algorithm TS-ACO to solve this problem.The classical ant colony algorithm uses spatial distance to select nodes,while TS-ACO considers the impact of both temporal and spatial distance on node selection.Meanwhile,we adopt Cordeau’s Multi-Depot Vehicle Routing Problem with Time Windows(MDVRPTW)dataset to evaluate the performance of our system.According to the experimental results,TS-ACO,which considers spatial and temporal distance,is more effective than the classical ACO,which only considers spatial distance. 展开更多
关键词 Dynamic vehicle routing multiple depots ant colony optimization temporal-spatial distance time slice
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Theoretical Logic and Practical Pathways for Distance Open Education Empowering the Enhancement of Digital Literacy among Rural Cadres
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作者 Ming LU Ji TANG Yuxiao ZHANG 《Asian Agricultural Research》 2026年第2期37-41,共5页
At present, enhancing the digital literacy of village cadres faces practical constraints such as governance capability gaps induced by the second-level digital divide, the absence of a systematic cultivation system, i... At present, enhancing the digital literacy of village cadres faces practical constraints such as governance capability gaps induced by the second-level digital divide, the absence of a systematic cultivation system, incomplete last-kilometer implementation for translating skills into practice, and inadequate incentive mechanisms. As a novel educational form deeply integrating digital information technology with teaching and learning, distance open education provides multi-directional empowerment for enhancing village cadres digital literacy. This is achieved through open learning methods, the application of modern digital technologies, tailored learning programs, and the establishment of "overpass bridges" for translating learning outcomes into practice. Based on this, it is essential to further streamline the pathways for educating and cultivating village cadres, vigorously promote the digitalization of teaching, practice, and support services, develop systematic and localized digital education resources, and actively explore and establish a complementary credit bank system for their digital literacy cultivation. 展开更多
关键词 Distance open education Digital literacy Village cadres Rural digital governance
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Quantitative investigation of well contact impact on single-event transient in sub-20 nm FinFET process
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作者 Qian Sun Bin Liang +12 位作者 Ya-Qing Chi Ming Tao Zhen-Yu Wu Hong-Xia Guo Wang-Yong Chen Jian-Jun Chen Peng-Cheng Huang Deng Luo Han-Han Sun Ya-Hao Fang Yu-Lin Gao Ming-Yan Ma Yang Guo 《Nuclear Science and Techniques》 2026年第3期105-118,共14页
This paper quantitatively discusses the influence of well contact on single-event transient(SET)in sub-20 nm FinFET by two-photon absorption(TPA)pulse laser.Two groups of inverter chains were designed to investigate t... This paper quantitatively discusses the influence of well contact on single-event transient(SET)in sub-20 nm FinFET by two-photon absorption(TPA)pulse laser.Two groups of inverter chains were designed to investigate the impact of well contact distance on the FinFET process.The experimental results show that the SET pulse width has a bimodal symmetric distribution,which is different from that of a bulk planar CMOS device.To investigate the detailed mechanism of the phenomenon,a high-precision FinFET TCAD model was established,in which both Id-Vd and Id-Vg errors were less than 10%compared to the SPICE model provided by the commercial process.TCAD simulation under heavy ion injection showed the mechanism of the abnormal phenomenon,where the well contact plays a major role in charge collection at the near-well contact distance,while the source plays a major role at the far distance.This phenomenon is completely different from that of planar CMOS devices.This indicates that the SET mechanism becomes more complicated during the FinFET process.Therefore,more effective SET hardening methods should be investigated for FinFET. 展开更多
关键词 FINFET Single-event transient(SET) Well contact distance Pulse laser
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